<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="utf-8"/>
        <title>01test</title>
        <script src="js/jquery-1.12.4.min.js"></script>
    </head>
    <body>
        <div id="box"></div>
    </body>
    <script>
        var oBox = $('#box');
        oBox.html('this is a div!');
        oBox.css('background','red');
        oBox.click( function () {
            alert(123);
        } )
    </script>
</html>